Battery assembly

Abstract

A battery stack is provided having lower and upper battery tiers each formed of at least two battery cell arrays. A pair of brackets are provided for connecting the lower arrays along a top surface of the lower tier and connecting the upper arrays to a bottom surface of the upper tier. The lower and upper battery tiers are secured together by the brackets without hardware mounted to an exterior surface of the stack.

What is claimed is: 
     
       1. A battery stack comprising:
 lower and upper battery tiers each formed of at least two battery cell arrays; 
 a plurality of array frames each housing one of the battery arrays; 
 a lower bracket connecting the lower arrays along a top surface of the lower tier; 
 an upper bracket connecting the upper arrays along a bottom surface of the upper tier; and 
 a plurality of fasteners each extending only through connection locations on the upper bracket and the lower bracket to connect the upper battery tier to the lower battery tier wherein the fasteners do not extend through any of the array frames, 
 wherein the lower and upper battery tiers are secured together by the brackets without the plurality of fasteners mounted to an exterior surface of the stack. 
 
     
     
       2. The battery stack of  claim 1  wherein each of the brackets has a same mounting footprint and wherein the footprints are aligned to secure the lower and upper tiers together, and allow airflow between the lower and upper battery tiers. 
     
     
       3. The battery stack of  claim 1  wherein the lower bracket comprises a top middle bracket and a pair of side brackets, wherein the top middle bracket connects the at least two lower battery arrays, and wherein the side brackets are spaced apart from the middle bracket and mounted to side regions on the lower battery tiers. 
     
     
       4. The battery stack of  claim 3  wherein the top middle bracket and the pair of side brackets are spaced apart to define lower openings, wherein the upper bracket includes a plurality of apertures formed therethrough, and wherein the lower openings and plurality of apertures allow airflow between the lower and upper battery tiers. 
     
     
       5. The battery stack of  claim 3  wherein the lower bracket is fastened to a top surface of the lower battery tier and the upper bracket is fastened to a bottom surface of the upper battery tier, wherein the mounting footprint of the lower bracket and upper bracket is the same, and wherein each mounting footprint includes a plurality of connection locations that align to connect the lower and upper battery tiers. 
     
     
       6. The battery stack of  claim 1 , wherein each of the array frames includes a pair of top rails and a pair of bottom rails and wherein the top and bottom rails are connected by a pair of opposing end plates. 
     
     
       7. The battery stack of  claim 6  wherein the lower arrays are connected by the top middle bracket along adjacent top rails of the array frames and wherein the upper arrays are connected by a tray along adjacent bottom rails of the array frames. 
     
     
       8. The battery stack of  claim 6  wherein each of the lower array frames includes at least one locating feature and each of the upper array frames includes at least one locating member that cooperates with the locating feature of a corresponding lower array frame to align the upper and lower battery tiers. 
     
     
       9. The battery stack of  claim 6  wherein the lower battery arrays are connected by the middle bracket along adjacent top rails of the array frames. 
     
     
       10. The battery stack of  claim 1  wherein the upper battery arrays are connected by a tray along adjacent bottom rails of the array frames. 
     
     
       11. The battery stack of  claim 1  wherein an access opening is defined in the upper battery tier such that a fastener is accessible through the access opening to fasten the upper and lower brackets. 
     
     
       12. A battery stack comprising:
 a lower battery tier having at least two lower arrays of battery cells connected together; 
 a top middle bracket connecting the two arrays and mounted to a top surface of the lower tier; 
 a pair of side brackets mounted along opposite side regions of the lower tier on the top surface of the lower tier; 
 an upper battery tier having at least two upper arrays of battery cells connected together; and 
 a bottom tray connecting the two upper arrays and mounted to a bottom surface of the upper tier, 
 wherein the bottom tray is aligned and fastened together with the top middle bracket and the pair of side brackets when the upper battery tier is mounted to the lower battery tier, thereby securing and aligning the lower and upper tiers together, and 
 wherein the brackets and bottom tray allow an airflow between the lower and upper battery arrays when the lower and upper battery tiers are secured together; 
 a plurality of fasteners, wherein an upper mounting footprint is defined by the bottom tray and a lower mounting footprint is defined by the top middle bracket and the side brackets, wherein the upper mounting footprint and lower mounting footprint are the same, wherein each mounting footprint includes a plurality of connecting locations that align to connect the lower and upper battery tiers, and wherein at least one of the fasteners extends through a connecting location defined in the top middle bracket and the bottom tray to secure the lower and upper battery tiers together; 
 a plurality of array frames each housing one of the arrays, wherein each of the array frames includes a pair of top rails and a pair of bottom rails, wherein the top and bottom rails are connected by a pair of opposing end plates, wherein the lower arrays are connected by the top middle bracket along adjacent top rails of the array frames and the upper arrays are connected by the bottom tray along adjacent bottom rails of the array frames, and wherein the plurality of fasteners extend only through the connection locations on the upper bracket and the lower bracket to connect the upper battery tier to the lower battery tier such that the fasteners do not extend through any of the array frames. 
 
     
     
       13. The battery stack of  claim 12  wherein an access opening is defined in the upper battery tier such that the connection location is accessible through the access opening to fasten the bottom tray and the top middle bracket together.